The Thermotech Men's Extreme Base Layer Top offers the heavyweight warmth, comfort and stretching you need to enjoy winter. This top is made from an Extreme polyester fabric that features ACCLIMATE Dry+ moisture management yarns to keep you dry, while the smooth outside makes it easy to layer. To give you extra warmth, this top has a lightly brushed fleece fabric inside, providing extra coziness for those cold days, while its odor blocking technology enhances freshness and odor control guaranteed for 20-30 washes. It is designed with an active fit with spandex, which makes it work as a base or middle layer. Thanks to its four-way stretch construction, this base layer provides no extra bulk as it hugs your body and moves with you, improving your performance. Stay warm and active all winter with the Thermotech Men's Extreme Base Layer Top!